Finding Vacuum Leak
Thread Starter
Instructor
Joined: Jul 2003
Posts: 217
Likes: 1
From: Atlanta GA
Finding Vacuum Leak
What is the best eay to find a vacuum leak. I have heard about the butane torch idea, but that sounds like an eyebrow burner. Is there a better way?
Thanks,
Larry...
Thanks,
Larry...
Le Mans Master
Joined: Feb 2000
Posts: 9,715
Likes: 27
From: Kempner Texas
Guys have their favorites, including the propane, etc. method. Don't be concerned about using the torch method. Remember, the torch is used un-lit.
I've tried several different methods and now simply use water from a garden hose. When the engine stumbles I know I've found the leak.
I'm just careful not to soak the electrical connectors, 02 sesnors or Opti.
Jake
I've tried several different methods and now simply use water from a garden hose. When the engine stumbles I know I've found the leak.
I'm just careful not to soak the electrical connectors, 02 sesnors or Opti.
Jake
Racer
Joined: Sep 2001
Posts: 266
Likes: 7
From: Sumner WA
I had a vacuum leak recently and tried several methods. On the hoses/tubes I used a mighty vac. Since I didn't find the leak I then used a propane torch which didn't detect anything. Finally I sprayed throttle body cleaner in different places and found my passenger side runner above #8 was the culprit. When I was stationed in Turkey I had to take a car to the mechanic for a vacuum leak and he used a re-purposed squeezable ketchup bottle full of water and sprayed it on things. It worked for him, but I couldn't find my leak using it. For me the throttle body cleaner has worked the best. I seem to recall someone posting that they caused a fire that way. I was more concerned with the propane torch causing a fire and never even considered it with the cleaner. Maybe I got lucky because nothing else I tried found my leak. I was certain my problems were caused by a vacuum leak and I finally recorded a data log using Datamaster and confirmed my suspicion. In the following picture you can see I'm running lean at low RPM and the IAC keeps moving to try to adjust for the lean condition.
Good luck,
Ron
Good luck,
Ron
Melting Slicks
Joined: Mar 2002
Posts: 3,108
Likes: 126
From: S.L.C. UT
I just use a can of carb cleaner. The rpm comes up and you found it. And the other part of finding vacuum leaks is to pinch off vacuum hoses. Sometimes something fed from a vacuum line can also leak.
